For the bar stool, I cut a 3" x 3" square. I used balsa wood since this is essentially a temporary project. For a permanent project, I would use regular pine or maple. An easy trick for spacing the legs for a chair or table is to use a small square. In this case I used a 1/2" (approx. 1 cm) wood craft square. Trace the square in each corner of the bottom of your furniture, then use a ruler to make an X in the square, and you'll have perfect placement of the furniture legs.